Malignant tumors metastasize. Meaning, little pieces shoot off and attach to other places. Lungs are usually the first place where new tumors grow. And guinea pigs are small enough, it's easy to do full-body x-rays. I would wait until after the incision is healed, though.

Let me put it to you this way...all tumors like that have a blood supply. There were tiny blood vessels traveling through that tumor to keep it "alive". Before it was removed, individual cells could have been sloughed off (broken off) and gone into the blood stream. Those cells could end up anywhere.

This is the first time I hear about those tests. Briana's vet is obviously excellent, and I wonder why he didn't suggest them. Briana, did you discuss that with him? I'm asking because it seems odd that no one here has ever been suggested them before.

I'm taking my Petunia to see Dr. Murray today. He called me last week to explain to me the theory on using Polycitra for stones in pigs. I have found that he is clear about his thinking on things. He shares his thought process if you can catch him...

Description
Representative sections of the mass are examined. The mass is present subjacent to the teat. It is fairly well demarcated but nonencapsultated and is surrounded by a peripheral margin of normal tissue ringing from .03cm and more.

The center portion of the mass consists of small tubules and cluster formed by mildly atypical cuboidal epithelial cells. Narrow bands of fibrous stroma are interspersed and the mitotic rate is approximately 1/hpf. Some of the tubules contain luminal secretory material.

There are also multifocal areas of necrosis and inflammation present within the mass. In some areas, there is also a prominent mycepithelia stroma between epithelia structures.

Comments: Mammary neoplasm's can occur in both male and female guinea pigs. The majority of mammary tumors in guinea pigs are consistent with benign fibroadenomas. Approximately 30% are adenocarcinoma, as in this case.

They generally behave as local invasive tumors with rare metastasis reported. In this case, the mass was fairly well demarcated and appeared within surgical margins. This would suggest complete removal; however findings should be used in conjunction with surgical findings.

Lymphatic and/or vascular invasion were not identified; however, I cannot guarantee that they have not yet taken place.

Close monitoring of the mammary region for re-growth is suggested as well as monitoring of regional lymph nodes for any sign on enlargement that would suggest metastasis.